Elimination+2A

Lenea H. Elimination Method

23. Using the elimination method to solve a system of equations goes against the rules of algebra because you are not adding or subtracting the same thing from both sides.

Always True Sometimes True Never True

Answer: False

Examples:

3x- y= 12 2x +y= 13

3x-y=12 + 2x +y=13 5x= 25 (y cancels out) 5x= 25 x= 5

(Substitue for x to find y) 5(5)-y=12 25-y= 12 -25 -25 -y = -13 y = 13 (5,13)

Collaborators: none.


 * Sophia Moreno

17.** Using the elimination method to solve a system of equations goes against the rules of algebra because you are not adding or subtracting the same thing from both sides. o False

It’s just combining two equations. It like when one side of an equation has -1 and the other has +1. They cancel each other out. With systems; the two sides are separate equations.

Jasmine Thomas

This problem was solved by using the elimination method.

5x-4y=7 2y+6x=22

The key thing to remember here is that you need to have a balance in both equations in order for this method to work. Example: If you multiply on number in the equation by "3" you have to multiply all. If there is an imbalance this method will not work.

The good thing about this method is that you have the option of using any number you want to multiply your equations by.

This system of equations was solved by using the substitution method

5x-4y=710x-8y=14 (this equation was multiplied by 2) 2y+6x=22---24x+8y=88 (this equation was multiplied by 4)

After you have lined your equations up vertically so that the variables match one another you then add the top and the bottom.

When you added the two equations together you got... 34x=102 (The 8's canceled one another out because they were the same number but with opposite signs, this was done so we could isolate x and then eventually solve for it)

Now you should see that you divide 34/102 and your answer is X=3.

We are not done yet. Now you know what "X" is you can replace it in the equations, so basically wherever there is an "X" you should replace it with 3.

6(3)+2y=22 18+2y=22

Subtract 18 from both sides of the equation and you are left with
 * 2y=4**

Now you should divide both sides of the equation by 2 so you can isolate "Y"

And then your answer is **Y=2**